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951.
The morphology and ultrastructure of aJaponochytrium sp. has been studied by light, scanning and transmission electron microscopy. The wall has been shown to be multilamellate and persistent. Stages in zoospore cleavage are described and sagenogenetosomes reported in mature sporangia. 相似文献
952.
Chikungunya virus vaccines prepared by Tween 80 and ether inactivation of virus grown in green monkey kidney cell cultures were shown to be as immunogenic as comparable Formalin-inactivated vaccines. Both types of vaccine stimulated hemagglutination-inhibiting, complement-fixing, and neutralizing antibody and afforded protection to mice against a live virus challenge. It was shown after Tween-ether treatment of chikungunya virus that the infectivity of the virus was lost and the hemagglutinin titer was increased. By characterization of the resultant hemagglutinin by sucrose and cesium chloride density gradient centrifugation, it was found that the extracted particle was smaller in size and greater in density than the parent virus particle. Removal of lipid may account for the alterations in the physical characteristics of the infectious virus particle. Conditions for treatment of chikungunya virus with Tween and ether were found that preserved high titers of hemagglutinin as well as the immunogenicity of the virus preparations. 相似文献
953.
E. F. Harrison P. Zwadyk Jr. R. J. Bequette E. E. Hamlow P. A. Tavormina W. A. Zygmunt 《Applied microbiology》1970,19(5):746-750
Haloprogin was shown to be a highly effective agent for the treatment of experimentally induced topical mycotic infections in guinea pigs. Its in vitro spectrum of activity also includes yeasts, yeastlike fungi (Candida species), and certain gram-positive bacteria. The in vitro and in vivo antifungal activity of haloprogin against dermatophytes was equal to that observed with tolnaftate. The striking differences between the two agents were the marked antimonilial and selective antibacterial activities shown by haloprogin, contrasted with the negligible activities found with tolnaftate. Addition of serum decreased the in vitro antifungal activity of haloprogin to a greater extent than that of tolnaftate; however, diminished antifungal activity was not observed when haloprogin was applied topically to experimental dermatophytic infections. Based on its broad spectrum of antimicrobial activity, haloprogin may prove to be a superior topical agent in the treatment of dermatophytic and monilial infections in man. 相似文献
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958.
Occurrence of a 3′-phosphoadenosine 5′-Phosphosulphate synthesizing system In two Ochromonas species
The presence of an enzyme capable of incorporating 35SO42? into 3′-phosphoadenosine 5′-phosphosulphate has been demonstrated,in Ochromonas danica and O. malhamensis. This system probably includes the enzymes ATP:sulphate adenyltransferase. E.C. 2.7.7.4 and ATP:adenylsulphate 3′-phosphotransferase, E.C. 2.7.1.25. 相似文献
959.
Trisporic Acid Biosynthesis in Separate Plus and Minus Cultures of Blakeslea trispora: Identification by Mucor Assay of Two Mating-Type-Specific Components 总被引:1,自引:0,他引:1
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Richard P. Sutter Domenick A. Capage Thomas L. Harrison William A. Keen 《Journal of bacteriology》1973,114(3):1074-1082
Separate plus and minus cultures of Blakeslea trispora synthesize small amounts of trisporic acids under specific conditions. These amounts are expressed as a percentage of the trisporic acids (50 mg/liter of medium) synthesized by mixed plus-minus cultures in 5 days. Plus cultures, without additives from minus cultures, synthesize 0.1% trisporic acids. Plus cultures synthesize 0.4% trisporic acids when stimulated by M-factor, a mating-type-specific component synthesized by minus cultures. Minus cultures, without additives from plus cultures, do not synthesize even 0.0001% trisporic acids. Minus cultures synthesize 1% trisporic acids when stimulated by P-factor, a mating-type-specific component synthesized by plus cultures. Minus cultures synthesize M-factor when stimulated by pi, a component synthesized by plus cultures. We speculate that (i) minus cultures synthesize a component, mu, which stimulates P-factor synthesis in plus cultures, and (ii) both M-factor and P-factor are precursors of trisporic acids. 相似文献
960.
Measurements of heart rate, respiratory rate, surface temperature (Ts) and rectal temperature (Tre) of mature Coturnix quail were continuously recorded for 30 min at 25° and 38°C environmental temperatures. Ts and Tre increased to a maximum level within 16 and 20 min after exposure to the 38°C environment. Thermal panting was initiated after a 1.3°C rise in rectal temperature and 12 min of exposure to 38°C. Heart rate decreased consistently during the first 20 min at 38°C, then remained at the decreased level. The increase in heart rate at 38°C following atropine injection (0.1 mg/100 g body weight) and subsequent bilateral vagotomy indicated that the decrease in heart rate is the result of an increase in vagal tone and that both efferent and afferent vagi are involved in the decreased heart rate.
Scientific Paper No. 3454. College of Agriculture, Washington State University, Pullman. Project 1915.This investigation was supported in part by funds for medical and biological research by State of Washington Initiative Measure No. 171 and the Graduate School Research Funds. 相似文献
Zusammenfassung Herz- und Atemfrequenz, Oberflächen- und Rektaltemperatur erwachsener Wachteln wurden bei 25° und 38°C Raumtemperatur fortlaufend während 30 Min gemessen. Ts und Tre stiegen bei 38°C innerhalb 16–20 Min zu einem maximalen Wert an. Hecheln wurde nach 1,3°C Anstieg der Tre, 12 Min nach Exponierung bei 38°C gemessen. Die Herzfrequenz fiel gleichmässig während der ersten 20 Min bei 38°C und blieb auf diesem Niveau während der weiteren Expositionszeit. Der Anstieg der Herzfrequenz nach Injektion von Atropinsulfat (0,1 mg/100 g Kp.Gew.) und nachfolgender bilateraler Vagotomie zeigte, dass der Abfall der Herzfrequenz Folge eines erhöhten Vagotonus ist, und dass sowohl die afferenten als auch die efferenten Ä ste des Vagus beteiligt sind.
Resume On a enregistré de façon continue durant 30 min la fréquence des pulsations et de la respiration ainsi que les températures cutanée (TS) et rectale (Tre) de cailles adultes maintenues à des températures ambiantes de 25° et de 38°C. Les deux températures (Ts et Tre) augmentent durant 16 à 20 min après que les volailles aient été mises à 38°C, pour atteindre alors leur maximum. Les oiseaux commencent à haleter après que Tre ait augmenté de 1, 3°C, soit 12 min après le début de l'exposition à 38°C. La fréquence des pulsations diminue régulièrement durant les 20 premières minutes de l'exposition à 38°C et se maintient constante par la suite. La hausse de la fréquence des pulsations à 38°C consécutive à l'injection de sulfate d'atropine (0, 1 mg pour 100 g de poids du corps), suivie de vagotomie bilatérale, montre que la diminution observée de la dite fréquence est le résultat d'une augmentation du vagotonus et que les deux branches (afférente et efférente) du nerf vague y participant.
Scientific Paper No. 3454. College of Agriculture, Washington State University, Pullman. Project 1915.This investigation was supported in part by funds for medical and biological research by State of Washington Initiative Measure No. 171 and the Graduate School Research Funds. 相似文献